The electronic grade aqueous hydrogen peroxide solution can be used as cleaning agent for silicon pellet and as etching agent for printed circuit board, and also as the reagent for producing of electronic grade reagent such as high-purity silicic acid, so it is the indispensable electronic chemicals in electronic industry. The producing of the electronic grade aqueous hydrogen peroxide solution has a rapid development with the rapid development of the electronic industry, and with the trend of the integrated circuit's development to the miniaturization and high processing speed the requirements to the electronic aqueous hydrogen peroxide solution are more and more strictly. The conventional methods for producing the ultra-clean and high-purity aqueous hydrogen peroxide solution include Rectification, Resin Adsorption, Membrane separation, and Supercritical Fluid Extraction.
The Rectification which is the optimal method for removing inorganic impurities has a high yield and can be used for long production cycle. Both methods for producing the aqueous hydrogen peroxide solution disclosed by patent JP11292521(A) and JP2000001305(A) use the multilevel heating and evaporation to gas-liquid separation. US patent US005670028A discloses a process for preparing high purity hydrogen peroxide aqueous solution which includes the steps of distillation to remove the organic carbon impurities and inorganic impurities and vacuum rectification to obtain the aqueous hydrogen peroxide solution. US patent US005296104A disclosed a process for obtaining purified aqueous hydrogen peroxide solutions with the combination of rectification and washing. But, as we know, the rectification has a high energy consumption, the amount and the cost of the fluororesin as inner lining in the rectification tower is also high.
The Resin Adsorption used to produce of ultra-clean and high-purity aqueous hydrogen peroxide solution relates mostly to strong-acid cation exchange resin, strong-basic anion exchange resin and hydrophilic porous resin etc. And this method has high efficiency to remove impurities, low occupation of land, smart equipment combination and can obtain product of different purities. PCT patent WO98/54085A1 disclosed a method for preparing an ultrapure hydrogen peroxide solution by ion exchange in the present of ion acetate comprises at least cation-exchanging adsorbents and at least anion-exchanging adsorbents contains carboxylate ions of formula R—COO− and, particularly, acetate ions. US patent US005851505A disclosed a method with two-stage ion exchange resin in-line too. Japanese patents JP10259008(A) and JP10297909(A) separately disclosed a method for production of purified hydrogen peroxide solution with combination of strong acid cation-exchanging resin and strong basic anion-exchanging resin. However, these methods of Resin Adsorption have complex process and steps, and the consumption of resin is high.
Membrane separation with a promising prospect can be operated at room temperature and without phase transformation during production. Although the method has simple operation and high purity of product, but the operating life of the membrane is short and cost is higher because of frequently replacement of the membrane, so this method is used combined with other methods. Both the Chinese patent CN1189387C which disclosed a method for producing of high purity hydrogen peroxide and CN100420625C which disclosed a method for producing of electronic grade hydrogen peroxide use combination of ion exchanging resin and membrane filtration. And Chinese patent CN101244810A disclosed a method and equipment for producing of ultra-clean and high-purity hydrogen peroxide with combination of membrane filtration and absorbent charcoal and multi-stage rectification.
Supercritical Fluid Extraction, used by Kemirachemical Oy Company locates in Finland to removing organic impurities and producing hydrogen peroxide, is the method newly developed and has simple operation, high yield and low energy consumption. But this method has low purity of product.
There is also a method of Absorbent Charcoal for producing of electronic grade aqueous hydrogen peroxide solution such as the method disclosed in Japanese patent JP11035305(A) for production of purified aqueous hydrogen peroxide solution, i.e the charcoal is used for absorbing after it is pretreated and cleaned. But the charcoal will decompose the hydrogen peroxide.